A phase-space view of cold-gas properties of Virgo-cluster galaxies: multiple quenching processes at work?

Abstract

We investigate the cold-gas properties of massive Virgo galaxies (> 10 9 M ) at < 3R 200 (R 200 is the radius where the mean interior density is 200 times the critical density) on the projected phasespace diagram (PSD) with the largest archival dataset to date to understand the environmental effect on galaxy evolution in the Virgo cluster. We find: lower H i and H 2 mass fractions and higher starformation efficiencies (SFEs) from H i and H 2 in the Virgo galaxies than the field galaxies for matched stellar masses; the Virgo galaxies generally follow the field relationships between the offset from the main sequence of the star-forming galaxies [∆(MS)] with gas fractions and SFEs but slightly offset to lower gas fractions or higher SFEs than field galaxies at ∆(MS) < 0; lower gas fractions in galaxies with smaller clustocentric distance and velocity; lower gas fractions in the galaxies in the W cloud, a substructure of the Virgo cluster. Our results suggest the cold-gas properties of some Virgo galaxies are affected by their environment at least at 3R 200 maybe via strangulation and/or pre-processes and H i and H 2 in some galaxies are removed by ram pressure at < 1.5R 200 . Our data cannot rule the possibility of the other processes such as strangulation and galaxy harassment accounting for the gas reduction in some galaxies at < 1.5R 200 . Future dedicated observations of a mass-limited complete sample are required for definitive conclusions.

VERTICO: The Virgo Environment Traced In CO Survey

“…The cluster is dynamically young, contains significant substructure and is actively accreting members. This ensures Virgo's membership includes both infalling and virialised systems on a wide range of orbits throughout the cluster (Tully & Shaya 1984;Gavazzi et al 1999;Karachentsev et al 2014;Sorce et al 2016;Yoon et al 2017;Morokuma-Matsui et al 2021).…”